<div class="layui-form-item">
    <label class="layui-form-label">{$field.field_name}：</label>
    <div class="layui-input-block w19">
        <select name=" {$field.field_code}" td-selected="{$value}">
            <option></option>
            {volist name="param_list" id="param"}
            <option value="{$param.val}">{$param.key}</option>
            {/volist}
        </select>
    </div>
</div>